Washington, Feb 20 (AP) Back on track, Senate Republicans pushed ahead on Wednesday with their USD 340 billion budget bill focused on funding the White House's mass deportations and border security agenda after Vice-President JD Vance gave a green light to proceed despite a morning dust-up caused by President Donald Trump.

The package was in jeopardy after Trump publicly bashed the approach from the Senate Budget Committee chairman, Sen Lindsey Graham of South Carolina. Trump said he favoured the "big beautiful bill" from House Republicans, a more politically fraught package that includes USD 4.5 trillion in tax cuts but slashes government programmes and services. Senators want to address those priorities later, in a second package.

"We are moving forward," said Sen John Barrasso of Wyoming, the GOP whip, after a lunch meeting with Vance at the Capitol.

The start-stop process is complicating what's already a heavy legislative lift for Republicans, who have a rare sweep of power with majority control of Congress, but face big hurdles enacting Trump's agenda as Democrats prepare to counter with steep objections at every step.

Ongoing GOP divisions over whether to do one package or two -- the House thinks they can only muscle one package to passage, while the Senate believes two will be easier -- has created a push-pull dynamic that Trump is leveraging as he goads the two chambers of Congress to compete with each other.

Trump, in his own private talks with the senators, including last weekend at Mar-a-Lago, has essentially told them just to "get the result".

It all comes as Democrats, without the votes to stop Trump's plans, are warning Americans what's at stake.

"These bills that they have one purpose -- and that is they're trying to give a tax break to their billionaire buddies and have you, the average American person, pay for it," Senate Democratic leader Chuck Schumer of New York told AP.

Schumer convened a private call over the weekend with Democratic senators and agreed on a strategy to challenge Republicans for prioritising tax cuts that primarily flow to the wealthy at the expense of programme and service reductions in health care, scientific research, veterans services and elsewhere.

"This is going to be a long, drawn-out fight," Schumer said later.

With a party line vote, 50-47, the Senate launched the cumbersome budget process late on Tuesday and by Wednesday was slogging through an initial 50 hours of debate. That all leads up to an expected all-night session on Thursday with rapid-fire attempts to amend the package in what's typically called a "vote-a-rama".

The Republican package would allow USD 175 billion to be spent on border security, including money for mass deportation operations and building the US-Mexico border wall, in addition to a USD 150 billion boost to the Pentagon and USD 20 billion for the Coast Guard.

Trump border czar Tom Homan and top aide Stephen Miller told senators privately last week that they are running short of cash to accomplish the president's immigration and deportation priorities, spurring Republicans to move swiftly.

Eyeing ways to pay for it, Republican senators are considering a rollback of the Biden administration's methane emissions fee, which was approved by Democrats as part of climate change strategies in the Inflation Reduction Act, and hoping to draw new revenue from energy leases as they aim to spur domestic energy production.

But all that was in jeopardy when Trump said early on Wednesday he wanted the House's version passed as a way to "kickstart" the process.

Trump said, "Unlike the Lindsey Graham version of the very important Legislation currently being discussed, the House Resolution implements my FULL America First Agenda, EVERYTHING, not just parts of it!" The Senate's Republican leadership was blindsided by the post.

"As they say, I did not see that one coming," said Senate Majority Leader John Thune, R-SD.

Thune had engineered the two-bill approach as a way to deliver an early victory for the White House and had pushed the Senate forward while the House is away on recess this week, saying it was time to act.

By lunchtime, after Vance met with the senators, his message was for them to simply carry on.

Sen Kevin Cramer, R-ND, said afterward that Vance told them, "The president wants whatever you guys want. Just do whatever you want. He's going to support it." Cramer said Trump enjoys watching the House and Senate compete over his agenda.

The House GOP bill is multiple times larger, with USD 4.5 trillion in tax cuts and USD 1.5 trillion in spending reductions over the decade across Medicaid health care programmes, food stamps and other services used by large swaths of the country. The cuts could ultimately grow to USD 2 trillion to appease hard-right conservatives.

The budget plans are being considered under what's called the reconciliation process, which allows passage on a simple majority vote without many of the procedural hurdles that stall legislation. Once rare, reconciliation is increasingly being used in the House and Senate to pass big packages on party-line votes when one party controls the White House and Congress.

During Trump's first term, Republicans used the reconciliation process to pass GOP tax cuts in 2017. Democrats used reconciliation during the Biden presidency era to approve Covid relief and the Inflation Reduction Act. (AP) SZM